Transparent window films are adhered to glass window surfaces so as to reduce the amount of near infra-red, ultra-violet and/or visible radiation entering interior building space. Films are also provided so as to maintain heat in the interior space--that is, to reduce heat radiation loss through the window. The window films thus assist to minimize loads on the heating, ventilating and air conditioning (HVAC) system which services the building. Lower HVAC loads thereby translate into lower costs of hating or cooling the interior building space.
Such "solar control films" can have a variety of film structures. For example, one common type of solar film is a laminate structure having a base layer (e.g., a transparent polyester sheet, such as polyethylene terephthalate sheet) having a relatively thin, transparent solar reflective metallized deposit thereon. A protective layer (e.g., polyethylene terephthalate) may then be applied over the solar reflective layer. See, for example, U.S. Pat. No. 4,634,637, the entire content of which is expressly incorporated hereinto by reference.
Solar films are typically adhered physically to a surface of a glass window using a suitable transparent adhesive, such as those disclosed in U.S. Pat. Nos. 4,429,005 and 4,408,021, the entire content of each patent being incorporated expressly hereinto by reference. In general, the window films are cut to substantially cover the entire window glass area, except for a small border region between the edges of the film and the window frame (typically on the order of between about 1/16 inch to about 1/8 inch). In order to protect the metallized deposits or layers of the solar film from the degradative effects of window cleaners and other ambient atmospheric conditions (e.g., moisture and salt), it may be necessary to seal the edges of the window film with a suitable sealant. In this way, the sealant substantially minimizes (and most preferably prevents) degradative chemical attack on the individual metallized deposits or layers of the solar film so as to minimize (or prevent entirely) oxidation or corrosion which, in turn, allows to film to retain its appearance over its useful life.
Edge sealing of window films adhered to glass window surfaces can, however, be problematic. For example, in order to enhance the visual appearance of the finished edge-sealed solar film, the sealant should be transparent. Furthermore, only a relatively thin layer of the edge sealant should be applied so as to maintain its transparency. The edge sealant should not be too viscous as otherwise application would be difficult, while relatively non-viscous edge sealants tend to run along the edge of the glass preventing an adequate edge seal from being formed and potentially marring the visual appearance of the finished window.
Conventional edge sealants are applied in a number of ways, none of which is particularly effective. For example, edge sealants have been applied directly from a nozzle or spout of a container. These techniques, and the typical edge sealant employed, render it quite difficult to apply a thin, transparent seal along the entire edge of the window film which does not give rise to visual imperfections. The art therefore has clearly needed improved techniques to edge-seal window films, and it is toward providing such improved techniques that the present invention is directed.
Broadly, the present invention is directed toward kits and methods whereby transparent edge seals may be applied to window films adhered to window glass surfaces. More specifically, according to the present invention, window film (e.g., solar film) is edge-sealed by moving a porous applicator tip saturated with liquid sealant in wiping contact along an edge of the window film to be sealed so as to transfer a portion of the liquid sealant from the saturated applicator tip to the window film edge. Thereafter, the liquid sealant is allowed to dry so that a residue of the sealant (e.g., most preferably a solvated plastics material) remains as a transparent layer sealing the space between the window film edge and the adjacent window glass frame. Most preferably, one form of the present invention is a kit which includes a pen-like applicator and a container which contains a quantity of liquid sealant. The applicator is provided with the porous applicator tip at one end in fluid communication with a barrel defining an interior reservoir space. The reservoir space may thus be filled with a quantity of liquid sealant which is brought into fluid communication with the reservoir space so as to allow the liquid sealant to flow into the applicator tip and thereby saturate the same.
Further aspects and advantages of this invention will become more clear after careful consideration is given to the following detailed description of the preferred exemplary embodiments thereof.